1. Field of the Invention
Embodiments of the invention relate to a keyboard. More specifically, embodiments of the invention relate to a touch type keyboard having cursor control functions embedded in the home row.
2. Background
With the increasing ubiquity of mobile products, reduced sized keyboards are increasingly important. Various manufacturers have provided different types of keyboards, many of which are actually larger than the devices with which they communicate. Many keyboards provide a single layer of functions associated with particular location on the keyboard. As used herein, a “layer” refers to a character and the shift of the character. Thus, capital J and lowercase j are regarded as falling within a single layer as is commonly the case on standard touch-type keyboards. To make keyboards smaller, it can be desirable to overlap functions under the same location on the keyboard. Taken to its extreme, a typical phone keypad allows cycling through letters and symbols using multiple touches to cause the cycling. This however, does not permit efficient entry and does not constitute what is commonly regarded as a touch-typing keyboard. Generally, touch-typing keyboards are constrained by spacing between keys and single touch access to alphabetic characters. Common touch type patterns include QWERTY and AZERTY keyboards. But merely having e.g. a QWERTY pattern does not make a keyboard a touch-type keyboard. International touch typing standard requires spacing between keys to be 19 mm±1 mm. Smaller devices such as netbooks have compressed this limit, but the practical limitation for touch-typing appears to be a key spacing of greater than 14 mm. Most typists would need at least 17 mm spacing to touch type effectively.
In addition to alphanumeric keys, many existing keyboards provide additional keys for popular commonly used functions. Such functions include the cursor keys, that is the up, down, and right and left arrow keys commonly provided as dedicated keys, usually on the right side of the keyboard. Unfortunately, these cursor keys, while popular, occupy valuable real estate where form factor of the keyboard is constrained and increased cost to manufacture these additional structures must be provided. More importantly, these side-located cursor keys cause the user to leave home row frequently, which slows typing.